The closed injuries of the lower urinary tract: problems of the X-ray diagnostics. Results of X-ray investigation were analyzed in 54 patients with urinary bladder trauma and 23 patients with urethral injuries. There were no false conclusions during urography in 23 patients with urethral injuries. In one patient urography was carried out in late terms due to the underestimation of urether trauma by the time of admission to the hospital. Cystography was carried out in 38 out of 54 patients to exclude bladder trauma. Presence of trauma was confirmed in 36 (94,7%) cases. False conclusion about the absence of bladder rupture was given in 2 (5,26%) cases. Type of rupture was misdiagnosed in 5 (13,1%) patients leading to increased extent of operation in 1 case. The reasons for the false conclusions were misconduction of investigation technique and underestimation of the obtained X-ray data.